There is a continued interest in improving the performance characteristics of athletic shoes. Much of the recent industry interest continues to relate to the manufacture of footwear having energy return characteristics.
One type of energy return system employs the use of netting or a mesh arrangement in selected portions of the sole construction. For example, U.S. Pat. No. 5,070,629, issued Dec. 10, 1991, discloses an energy return system that includes a rigid frame with a set of monofilaments or fibers secured under tension across the frame. The monofilaments or fibers form a spring-like grid system that stores energy during the compression portions of the gait cycle and releases energy during the push-off phase of the gait cycle. U.S. Pat. No. 5,402,588, issued Apr. 4, 1995, U.S. Pat. No. 5,561,920, issued Oct. 8, 1996, U.S. Pat. No. 5,595,002, issued Jan. 21, 1997, U.S. Pat. No. 5,852,886, issued Dec. 29, 1998, and U.S. Pat. No. 5,974,695, issued Nov. 2, 1999 disclose various improvements to this spring-like energy return system, all of which are herein incorporated by reference in their entirety.
It is an object of the present invention to provide an improved energy return system for a shoe.